Local definition 12: Seasonal forecast monthly mean data for lagged systems

Octets Key Type Contents
41 localDefinitionNumber codetable ECMWF local GRIB use definition identifier. 12 = ECMWF seasonal forecast monthly mean data for lagged systems
42 class codetable Class
43 type codetable Type
44-45 stream codetable Stream
46-49 experimentVersionNumber ksec1expver Version number or experiment identifier. (4 ASCII characters, right justified)
50-51 perturbationNumber unsigned Ensemble member number. Control forecast is number 0, perturbed forecasts 1-nn.
52-53 systemNumber unsigned System number. The "scientific version" number.
0 = RD experiment, 1 - 65534 = operational version number, 65535 = missing
54-55 methodNumber unsigned Method number. Distinguishes scientifically different forecast ensembles (e.g. different calibration/bias correction)
0 = control integration (i.e. without data assimilation), 1 - 65534 = operational version number
56-59 verifyingMonth unsigned Verifying month (in format YYYYMM)
60 averagingPeriod unsigned Averaging period (eg 6-hour, 24-hour)
61-62 forecastMonth unsigned Forecast month
63-64 numberOfForecastsInEnsemble unsigned Number of forecasts in ensemble
65-68 indexingDate unsigned MARS archiving date (YYYYMMDD)
69-70 indexingTime unsigned MARS archiving time (HHMM)

( 1) For instantaneous fields, a monthly mean is the mean of the fields sampled at the specified averaging period.

( 2) For accumulated fields, a monthly mean is the mean rate of accumulation of the fields.